struct element{
       int label;
       int koristeno;
};
struct bt{
       element elements[10000];
};
typedef int cvor;
 
bt* InitB(int x, bt* T){
    if(T) delete T;
    T = new bt;
    for(int i = 0; i < 10000; i++)
        T->elements[i].koristeno = 0;
    T->elements[1].label = x;
    T->elements[1].koristeno = 1; 
    return T;
}//initB
 
void CreateLeftB(int x, cvor n, bt* T){
     if(T->elements[n].koristeno == 0 || T->elements[2*n].koristeno == 1) {
           cout << "Greska" << endl << endl;
           return;
     }
     T->elements[2*n].koristeno = 1;
     T->elements[2*n].label = x;
}//CreateLeftB
 
void CreateRightB(int x, cvor n, bt* T){
        if(T->elements[n].koristeno == 0 || T->elements[2*n+1].koristeno == 1){
        cout << "Greska" << endl << endl;
        return;
    }
    T->elements[2*n+1].koristeno = 1;
    T->elements[2*n+1].label = x;
}//CreateRightB
 
cvor LeftChildB(cvor n, bt* T){
     if(T->elements[n].koristeno == 0) 
           return 0;
     if(T->elements[2*n].koristeno == 1) 
           return 2*n;
     else return 0;
}//LeftCildB
 
cvor RightChildB(cvor n, bt* T){
     if(T->elements[n].koristeno == 0) return 0;
     if(T->elements[2*n+1].koristeno == 1) return 2*n+1;
     else return 0;
}//RightCildB
 
cvor ParentB(cvor n, bt* T){
     if(n == 1) return 0;
     if(n%2) n--;
     return n/2;
}//ParentB
 
int LabelB(cvor n, bt* T){
          return T->elements[n].label;
}//LabelB
 
void ChangeLabelB(int x, cvor n, bt* T){
     if(T->elements[n].koristeno == 0) return;
     T->elements[n].label = x;
}//ChangeLabelB
 
cvor RootB(bt* T){
     if(T->elements[1].koristeno == 0) return 0;
     return 1;
}//RootB
 
void DeleteB(cvor n, bt* T){
    T->elements[n].koristeno = 0;
        if (LeftChildB(n, T)) DeleteB(LeftChildB(n, T), T);
        if (RightChildB(n, T)) DeleteB(RightChildB(n, T), T);
}//DeleteB